There are many different types of metal coatings available today. The right type of coating will depend on the type of base metal, the environmental stress on the metal and the specifics need for the coating.
Of course, there may also be other factors to consider as well. For example, metal coatings used on an automotive part may be required for resistance to friction, helping to reduce wear and tear and extend the life of the component. A coating used for a medical implant may be selected to reduce the risk of infection, rejection or to speed up the process of the tissue and the implant fusing.
As a general guideline, all metal coatings have to be carefully selected based on the properties the final surface requires. Coatings are often selected for increased resistance to corrosion, increased weldability or assembly needs as well as for aesthetic reasons.
Corrosion Resistance
Any type of non-corrosive metal can be used as a coating. The most commonly used metals include aluminum, zinc, cadmium, cobalt-chromium and nickel-chromium.
These types of metal coatings are designed to have very low porosity and leave a very smooth, even surface. They can be further treated to create specific types of finishes including highly polished surfaces for use with equipment, medical and dental devices and even for decorative use.
Improved Performance
Specific types of metals can also be used for coatings to increase lubricity, decrease friction or to alter the electrical properties of the base metal in electronic components. This can include gold, silver, copper, titanium and in some specialized applications the use of lead.
There are also polymer coatings than be used on metal. These are often selected for their ability to reduce friction and to prevent corrosion, extending the life of the part or component.
